This invention relates to an apparatus for treating living wastewater which purifies water to be treated such as living miscellaneous wastewater in general homes, human waste, urban drains and the like to evaporate and emanate the treated water into the atmosphere.
As a combined sewage purifier for purifying water to be treated such as living miscellaneous wastewater, urban drains and the like, an evaporation and emanation type wastewater treating apparatus has been used. A conventional evaporation and emanation type wastewater treating apparatus heretofore known is designed as shown in FIG. 10 where cobble stones 2, gravel 3 and sand 4 are layered in that order within a concrete treating vessel 1, a sediment layer such as soil 5 is laminated on the upper surface of the sand 4 through a Saran netting 8, a wastewater introducing pipe 6 is disposed so that the extreme end thereof reaches the bottom of the treating vessel, and a plant 7 for evaporating and emanating the treated water to the ground surface is planted.
In this apparatus, as a water level rises, the waste water introduced into the bottom of the treating vessel by passing through the wastewater introducing pipe 6 successively permeates into the cobble stones 2, gravel 3, sand 4 and soil 5, the water is treated and purified in the course that the wastewater is moved upward by the capillary action, and when approaching the ground surface, the water is absorbed by the roots of grasses and trees, and the wastewater is evaporated and emanated from pores of the plants due to plant photosynthesis and adjustment of temperature. A part of the wastewater evaporates and emanates also from the ground surface. An organic material decomposer such as bacteria which decomposes an organic material to change it into a water soluble material which can be easily absorbed by the roots as nutriments is present whereby an organic residue or mineral (inorganic material) are treated.
However, the above-described conventional natural evaporation and emanation system involves an important problem in that the evaporation and emanation power and decomposition power are affected by natural conditions. For example, the trees, grasss or the like enter a repose period in a winter season where their pores are closed and as a result, the metabolic activity stops. Therefore, the evaporation and emanation through the plant stops, and the activity of the organic material decomposer such as bacteria in the vicinity of the root is also reduced, and the decomposition of the residual organic material is delayed. A further problem is posed in that a portion directly evaporated and emanated from the ground surface is formed into a frozen soil due to insufficient supply of evaporation latent heat or into a state under snow, thus lowering the evaporation power of the ground surface. This trend comprises a problem inherently occuring as natural conditions in areas other than the tropics to one degree or another.